Factors influencing hydroids (Cnidaria: Hydrozoa) biodiversity and distribution in Arctic kelp forest

2008 ◽  
Vol 88 (8) ◽  
pp. 1567-1575 ◽  
Author(s):  
Marta Ronowicz ◽  
Maria Wlodarska-Kowalczuk ◽  
Piotr Kuklinski
Keyword(s):  
Kelp Forest ◽  
Distribution Patterns ◽  
Sediment Concentration ◽  
Saccharina Latissima ◽  
Kelp Forests ◽  
Laminaria Digitata ◽  
Alaria Esculenta ◽  
Algal Host ◽  
A Site ◽  
West Spitsbergen

The biodiversity and distribution patterns of epiphytic hydroids were studied in kelp forests (composed of Laminaria digitata, Saccharina latissima and Alaria esculenta) located in an Arctic glaciated fiord (Hornsund, west Spitsbergen). In total, twenty-eight species were found colonizing algae, stones connected to holdfast, and overgrowing the surface of other animals associated with kelps. The characteristics of the algal host (e.g. algae species, age, rhizoid volume or biomass) did not show any effect upon hydroid species richness or species composition. High hydroid biodiversity was strongly dependent on microsubstrate heterogeneity. The highest biodiversity as well as frequency of hydroid occurrence were noted at a site located furthest from the glacier and characterized by the lowest sediment concentration and sedimentation rate. Sexual reproduction also seemed to be inhibited by glacier-derived disturbance. Of ten fertile species found at the ‘clearest’ site only two were fertile at sites under the strong influence of such perturbations. Potential physical drivers of species occurrence were linked to the activity of tidal glaciers, particularly to high loads of mineral sedimentation and iceberg scouring.

Detecting Alaria esculenta and Laminaria digitata (Laminariales, Phaeophyceae) gametophytes in red algae, with consideration of distribution patterns in the intertidal zone

Phycologia ◽  
2018 ◽  
Vol 57 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Trevor T. Bringloe ◽  
Charlotte A.B. Bartlett ◽  
Emma S. Bergeron ◽  
Katherine S.A. Cripps ◽  
Nicole J. Daigle ◽  
...  
Keyword(s):  
Red Algae ◽  
Intertidal Zone ◽  
Distribution Patterns ◽  
Laminaria Digitata ◽  
Alaria Esculenta

scholarly journals Climate-driven shifts in species' distributions may exacerbate the impacts of storm disturbances on North-east Atlantic kelp forests

2016 ◽  
Vol 67 (1) ◽  
pp. 65 ◽  
Author(s):  
Dan A. Smale ◽  
Thomas Vance
Keyword(s):  
Kelp Forest ◽  
Species Distributions ◽  
Wave Action ◽  
Saccharina Latissima ◽  
Kelp Forests ◽  
Storm Damage ◽  
Laminaria Hyperborea ◽  
East Atlantic ◽  
North East ◽  
The North

Physical disturbance through wave action is a major determinant of kelp forest structure. The North-east Atlantic storm season of 2013–14 was unusually severe; the south coast of the UK was subjected to 6 of the 12 most intense storms recorded in the past 5 years. Inshore significant wave heights and periods exceeded 7m and 13s with two storms classified as ‘1-in-30 year’ events. We examined the impacts of the storm season on kelp canopies at three study sites. Monospecific canopies comprising Laminaria hyperborea were unaffected by storm disturbance. However, at one study site a mixed canopy comprising Laminaria ochroleuca, Saccharina latissima and L. hyperborea was significantly altered by the storms, due to decreased abundances of the former two species. Quantification of freshly severed stipes suggested that the ‘warm water’ kelp L. ochroleuca was more susceptible to storm damage than L. hyperborea. Overall, kelp canopies were highly resistant to storm disturbance because of the low vulnerability of L. hyperborea to intense wave action. However, if climate-driven shifts in kelp species distributions result in more mixed canopies, as predicted, then resistance to storm disturbance may be eroded.

scholarly journals Variability and Potential of Seaweeds as Ingredients of Ruminant Diets: An In Vitro Study

Animals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 851 ◽  
Author(s):  
Ana de la Moneda ◽  
Maria Dolores Carro ◽  
Martin R. Weisbjerg ◽  
Michael Y. Roleda ◽  
Vibeke Lind ◽  
...  
Keyword(s):  
Control Diet ◽  
In Vitro Study ◽  
Saccharina Latissima ◽  
Palmaria Palmata ◽  
Ruminal Fermentation ◽  
Laminaria Digitata ◽  
Alaria Esculenta ◽  
Ruminant Diets ◽  
Mastocarpus Stellatus

This study was designed to analyze the chemical composition and in vitro rumen fermentation of eight seaweed species (Brown: Alaria esculenta, Laminaria digitata, Pelvetia canaliculata, Saccharina latissima; Red: Mastocarpus stellatus, Palmaria palmata and Porphyra sp.; Green: Cladophora rupestris) collected in Norway during spring and autumn. Moreover, the in vitro ruminal fermentation of seventeen diets composed of 1:1 oat hay:concentrate, without (control diet) or including seaweeds was studied. The ash and N contents were greater (p < 0.001) in seaweeds collected during spring than in autumn, but autumn-seaweeds had greater total extractable polyphenols. Nitrogen in red and green seaweeds was greater than 2.20 and in brown seaweeds, it was lower than 1.92 g/kg DM. Degradability after 24 h of fermentation was greater in spring seaweeds than in autumn, with Palmaria palmata showing the greatest value and Pelvetia canaliculata the lowest. Seaweeds differed in their fermentation pattern, and autumn Alaria esculenta, Laminaria digitata, Saccharina latissima and Palmaria palmata were similar to high-starch feeds. The inclusion of seaweeds in the concentrate of a diet up to 200 g/kg concentrate produced only subtle effects on in vitro ruminal fermentation.

Mechanisms leading to recruitment inhibition of giant kelp Macrocystis pyrifera by an understory alga

2021 ◽  
Vol 657 ◽  
pp. 59-71
Author(s):  
BA Beckley ◽  
MS Edwards
Keyword(s):  
Field Experiments ◽  
Local Community ◽  
Kelp Forest ◽  
Macrocystis Pyrifera ◽  
Forest Recovery ◽  
Kelp Forests ◽  
Giant Kelp ◽  
Combined Effects ◽  
Life Stages ◽  
Survival And Growth

The forest-forming giant kelp Macrocystis pyrifera and the communities it supports have been decreasing across their native ranges in many parts of the world. The sudden removal of giant kelp canopies by storms increases space and light for the colonization by understory macroalgae, such as Desmarestia herbacea, which can inhibit M. pyrifera recovery and alter local community composition. Understanding the mechanisms by which algae such as D. herbacea interact with M. pyrifera can provide insight into patterns of kelp forest recovery following these disturbances and can aid in predicting future community structure. This study experimentally tested the independent and combined effects of two likely competitive mechanisms by which D. herbacea might inhibit recovery of M. pyrifera in the Point Loma kelp forest in San Diego, California (USA). Specifically, we conducted field experiments to study the individual and combined effects of shade and scour by D. herbacea on the survival of M. pyrifera microscopic life stages, and the recruitment, survival, and growth of its young sporophytes. Our results show that scour had the strongest negative effect on the survival of M. pyrifera microscopic life stages and recruitment, but shade and scour both adversely affected survival and growth of these sporophytes as they grew larger. Canopy-removing storms are increasing in frequency and intensity, and this change could facilitate the rise of understory species, like D. herbacea, which might alter community succession and recovery of kelp forests.

A general method for determining translocation velocity in Laminariales

1981 ◽  
Vol 59 (2) ◽  
pp. 132-136 ◽  
Author(s):  
Richard G. Buggeln
Keyword(s):  
Pulse Method ◽  
Blade Surface ◽  
Laminaria Digitata ◽  
Incubation Chamber ◽  
Photoassimilate Translocation ◽  
Alaria Esculenta ◽  
Meristematic Region ◽  
Translocation Velocity ◽  
Distance Transport ◽  
General Method

The nondestructive pulse method for studying 14C-labelled photoassimilate translocation in Alaria esculenta has been adapted for species of Laminariales with flat, thick blades, in this case, Laminaria digitata. A 1-h pulse of [14C]bicarbonate(25 μCi) was applied to one side of the blade surface via a 12 mm diameter by 22 mm high, closed cylindrical incubation chamber. The upper 20-mm closed portion of the chamber was removed after the incubation period, the lower 2-mm open portion remained glued to the blade surface during the subsequent translocation period. A Geiger-Müller (G-M) detector probe with a 50 mm diameter end-window was used to measure the disappearance of radioactive organic matter from the pulsed region over the next 11–12 days. Accurate monitoring of the movement of 14C-labelled solutes through the cortex and into the medulla was confounded by changing absorption of radioactivity by the cortex. Uniform absorption was achieved once the translocatable radioactivity reached the medullary conducting cells (sieve filaments). Thus arrival and accumulation of 14C-labelled assimilate in the blade sink (meristem) was reliably measured with the G-M probe. For Laminaria digitata, the translocation velocity of the moving solute front was 1.7 cm∙h−1. The specific mass transfer of carbon was estimated at 0.4 mg C∙week−1∙mm−2 cross-sectioned medulla. Fifty-seven percent of assimilated carbon was exported in 10 days; 97% of the 14C remaining in the source was in insoluble matter and 3% was in soluble matter. Cutting sieve filaments on the sink side of the incubation chamber did not stop short distance transport through the cortex, but significant 14C-labelled photoassimilate was apparently unable to be re-routed around the cut as no radioactivity was detected in the sink area, the meristematic region at the base of the blade.

scholarly journals Valuation of kelp forest ecosystem services in the Falkland Islands: A case study integrating blue carbon sequestration potential

One Ecosystem ◽  
2021 ◽  
Vol 6 ◽  
Author(s):  
Daniel Bayley ◽  
Paul Brickle ◽  
Paul Brewin ◽  
Neil Golding ◽  
Tara Pelembe
Keyword(s):  
Ecosystem Services ◽  
Kelp Forest ◽  
Blue Carbon ◽  
Falkland Islands ◽  
Kelp Forests ◽  
Storm Damage ◽  
Ecological Processes ◽  
True Value ◽  
Sequestration Potential

Kelp forests provide many important ecosystem services to people, including mitigating storm damage, cycling nutrients, and providing commercially-harvestable resources. However, kelp forests’ ability to sequester carbon dioxide, and therefore help regulate the climate, has until recently, been overlooked in assessments of the beneficial services they provide. In this study we incorporate updated knowledge on the potential of kelp to sequester ‘blue carbon’, and use the extensive kelp forests of the Falkland Islands as a case study to assess the value of kelp forest to society through multiple associated ecosystem services. Our analysis shows kelp forests provide a highly valuable range of direct and indirect services, which if managed correctly, will continue to benefit people, both now and in the future. The total estimated value of the Falkland Islands’ kelp system is currently equivalent to ~ £2.69 billion per year (or £3.24 million km-2 year-1). However, the true value of the kelp forest surrounding the Falkland Islands is likely to be higher still, given that our estimate does not account for elements such as associated scientific research, tourism, and cultural services, due to the necessary data currently being unavailable. Similarly, the full value of these highly biodiverse ecosystems in supplying habitat and food to a large range of associated species is crucial, yet extremely difficult to fully quantify. This study illustrates the importance of maintaining kelp ecosystems in a healthy state to ensure they continue to supply valuable ecological processes, functional roles, and ecosystem services, including their overlooked role as significant long-term carbon sinks.

scholarly journals Evaluation of Various Perimeter Barrier Products

2021 ◽  
Author(s):  
Rabin Bhattarai ◽  
◽  
Yufan Zhang ◽  
Jacob Wood ◽  
◽  
...  
Keyword(s):  
Large Scale ◽  
Sediment Concentration ◽  
Department Of Transportation ◽  
Vegetative Cover ◽  
Buffer Strip ◽  
Erosion Rates ◽  
Sediment Removal ◽  
Loam Soil ◽  
A Site ◽  
Large Scale Tests

Construction activities entail substantial disturbance of topsoil and vegetative cover. As a result, stormwater runoff and erosion rates are increased significantly. If the soil erosion and subsequently generated sediment are not contained within the site, they would have a negative off-site impact as well as a detrimental influence on the receiving water body. In this study, replicable large-scale tests were used to analyze the ability of products to prevent sediment from exiting the perimeter of a site via sheet flow. The goal of these tests was to compare products to examine how well they retain sediment and how much ponding occurs upstream, as well as other criteria of interest to the Illinois Department of Transportation. The products analyzed were silt fence, woven monofilament geotextile, Filtrexx Siltsoxx, ERTEC ProWattle, triangular silt dike, sediment log, coconut coir log, Siltworm, GeoRidge, straw wattles, and Terra-Tube. Joint tests and vegetated buffer strip tests were also conducted. The duration of each test was 30 minutes, and 116 pounds of clay-loam soil were mixed with water in a 300 gallon tank. The solution was continuously mixed throughout the test. The sediment-water slurry was uniformly discharged over an 8 ft by 20 ft impervious 3:1 slope. The bottom of the slope had a permeable zone (8 ft by 8 ft) constructed from the same soil used in the mixing. The product was installed near the center of this zone. Water samples were collected at 5 minute intervals upstream and downstream of the product. These samples were analyzed for total sediment concentration to determine the effectiveness of each product. The performance of each product was evaluated in terms of sediment removal, ponding, ease of installation, and sustainability.

scholarly journals Disturbance intensity, disturbance extent and ocean climate modulate kelp forest understory communities

2020 ◽  
Vol 651 ◽  
pp. 57-69
Author(s):  
T Wernberg ◽  
M Couraudon-Réale ◽  
F Tuya ◽  
M Thomsen
Keyword(s):  
Functional Groups ◽  
Kelp Forest ◽  
Forest Understory ◽  
Small Scale ◽  
Kelp Forests ◽  
Ocean Climate ◽  
Disturbance Regimes ◽  
Disturbance Intensity ◽  
Control Community ◽  
Understory Communities

Disturbances often control community structure by removing large dominant species, allowing new species to colonize. Disturbances vary in intensity and extent, and their effects on resident communities can depend on local environmental conditions. We tested the effects of disturbance intensity and extent on different functional groups of understory species in kelp forests at 4 locations along an ocean climate gradient in Western Australia. We hypothesized that, compared to intact canopies, increasing disturbance intensities (50 and 100% of kelp removal) and extents (2, 4 and 8 m diameter) would promote light-dependent competitors (turf, foliose, articulated coralline and fucoid seaweeds) at the expense of less light-dependent functional groups (invertebrates and encrusting seaweeds). We also hypothesized that these effects would be most pronounced at warmer relative to cooler locations, where metabolic and ecological rates are faster. The first hypothesis was supported; light-dependent understory groups (turfs, in particular) increased, while less light-dependent groups (crusts in particular) decreased with increasing disturbance regimes. However, the second hypothesis was not supported; even though understory communities differed between locations and turf covers were highest at the warmest location, we found no significant interactions between locations and disturbance regimes. Importantly, our results revealed that even small-scale partial canopy loss can have significant effects on kelp-associated communities. The implied community-wide, density-dependent effects have implications for the management and conservation of kelp forests, because restoration of ecological functions must also consider the density of kelp forests, not simply their presence or absence.

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